diff -r 000000000000 -r d970ebf37754 wp/wp-includes/kses.php --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/wp/wp-includes/kses.php Wed Nov 06 03:21:17 2013 +0000 @@ -0,0 +1,1474 @@ + + * + * @package External + * @subpackage KSES + * + */ + +/** + * You can override this in a plugin. + * + * The wp_kses_allowed_html filter is more powerful and supplies context. + * CUSTOM_TAGS is not recommended and should be considered deprecated. + * + * @see wp_kses_allowed_html() + * + * @since 1.2.0 + */ +if ( ! defined( 'CUSTOM_TAGS' ) ) + define( 'CUSTOM_TAGS', false ); + +if ( ! CUSTOM_TAGS ) { + /** + * Kses global for default allowable HTML tags. + * + * Can be override by using CUSTOM_TAGS constant. + * + * @global array $allowedposttags + * @since 2.0.0 + */ + $allowedposttags = array( + 'address' => array(), + 'a' => array( + 'href' => true, + 'rel' => true, + 'rev' => true, + 'name' => true, + 'target' => true, + ), + 'abbr' => array(), + 'acronym' => array(), + 'area' => array( + 'alt' => true, + 'coords' => true, + 'href' => true, + 'nohref' => true, + 'shape' => true, + 'target' => true, + ), + 'article' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'aside' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'b' => array(), + 'big' => array(), + 'blockquote' => array( + 'cite' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'br' => array(), + 'button' => array( + 'disabled' => true, + 'name' => true, + 'type' => true, + 'value' => true, + ), + 'caption' => array( + 'align' => true, + ), + 'cite' => array( + 'dir' => true, + 'lang' => true, + ), + 'code' => array(), + 'col' => array( + 'align' => true, + 'char' => true, + 'charoff' => true, + 'span' => true, + 'dir' => true, + 'valign' => true, + 'width' => true, + ), + 'del' => array( + 'datetime' => true, + ), + 'dd' => array(), + 'details' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'open' => true, + 'xml:lang' => true, + ), + 'div' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'dl' => array(), + 'dt' => array(), + 'em' => array(), + 'fieldset' => array(), + 'figure' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'figcaption' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'font' => array( + 'color' => true, + 'face' => true, + 'size' => true, + ), + 'footer' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'form' => array( + 'action' => true, + 'accept' => true, + 'accept-charset' => true, + 'enctype' => true, + 'method' => true, + 'name' => true, + 'target' => true, + ), + 'h1' => array( + 'align' => true, + ), + 'h2' => array( + 'align' => true, + ), + 'h3' => array( + 'align' => true, + ), + 'h4' => array( + 'align' => true, + ), + 'h5' => array( + 'align' => true, + ), + 'h6' => array( + 'align' => true, + ), + 'header' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'hgroup' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'hr' => array( + 'align' => true, + 'noshade' => true, + 'size' => true, + 'width' => true, + ), + 'i' => array(), + 'img' => array( + 'alt' => true, + 'align' => true, + 'border' => true, + 'height' => true, + 'hspace' => true, + 'longdesc' => true, + 'vspace' => true, + 'src' => true, + 'usemap' => true, + 'width' => true, + ), + 'ins' => array( + 'datetime' => true, + 'cite' => true, + ), + 'kbd' => array(), + 'label' => array( + 'for' => true, + ), + 'legend' => array( + 'align' => true, + ), + 'li' => array( + 'align' => true, + 'value' => true, + ), + 'map' => array( + 'name' => true, + ), + 'menu' => array( + 'type' => true, + ), + 'nav' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'p' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'pre' => array( + 'width' => true, + ), + 'q' => array( + 'cite' => true, + ), + 's' => array(), + 'span' => array( + 'dir' => true, + 'align' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'section' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'small' => array(), + 'strike' => array(), + 'strong' => array(), + 'sub' => array(), + 'summary' => array( + 'align' => true, + 'dir' => true, + 'lang' => true, + 'xml:lang' => true, + ), + 'sup' => array(), + 'table' => array( + 'align' => true, + 'bgcolor' => true, + 'border' => true, + 'cellpadding' => true, + 'cellspacing' => true, + 'dir' => true, + 'rules' => true, + 'summary' => true, + 'width' => true, + ), + 'tbody' => array( + 'align' => true, + 'char' => true, + 'charoff' => true, + 'valign' => true, + ), + 'td' => array( + 'abbr' => true, + 'align' => true, + 'axis' => true, + 'bgcolor' => true, + 'char' => true, + 'charoff' => true, + 'colspan' => true, + 'dir' => true, + 'headers' => true, + 'height' => true, + 'nowrap' => true, + 'rowspan' => true, + 'scope' => true, + 'valign' => true, + 'width' => true, + ), + 'textarea' => array( + 'cols' => true, + 'rows' => true, + 'disabled' => true, + 'name' => true, + 'readonly' => true, + ), + 'tfoot' => array( + 'align' => true, + 'char' => true, + 'charoff' => true, + 'valign' => true, + ), + 'th' => array( + 'abbr' => true, + 'align' => true, + 'axis' => true, + 'bgcolor' => true, + 'char' => true, + 'charoff' => true, + 'colspan' => true, + 'headers' => true, + 'height' => true, + 'nowrap' => true, + 'rowspan' => true, + 'scope' => true, + 'valign' => true, + 'width' => true, + ), + 'thead' => array( + 'align' => true, + 'char' => true, + 'charoff' => true, + 'valign' => true, + ), + 'title' => array(), + 'tr' => array( + 'align' => true, + 'bgcolor' => true, + 'char' => true, + 'charoff' => true, + 'valign' => true, + ), + 'tt' => array(), + 'u' => array(), + 'ul' => array( + 'type' => true, + ), + 'ol' => array( + 'start' => true, + 'type' => true, + ), + 'var' => array(), + ); + + /** + * Kses allowed HTML elements. + * + * @global array $allowedtags + * @since 1.0.0 + */ + $allowedtags = array( + 'a' => array( + 'href' => true, + 'title' => true, + ), + 'abbr' => array( + 'title' => true, + ), + 'acronym' => array( + 'title' => true, + ), + 'b' => array(), + 'blockquote' => array( + 'cite' => true, + ), + 'cite' => array(), + 'code' => array(), + 'del' => array( + 'datetime' => true, + ), + 'em' => array(), + 'i' => array(), + 'q' => array( + 'cite' => true, + ), + 'strike' => array(), + 'strong' => array(), + ); + + $allowedentitynames = array( + 'nbsp', 'iexcl', 'cent', 'pound', 'curren', 'yen', + 'brvbar', 'sect', 'uml', 'copy', 'ordf', 'laquo', + 'not', 'shy', 'reg', 'macr', 'deg', 'plusmn', + 'acute', 'micro', 'para', 'middot', 'cedil', 'ordm', + 'raquo', 'iquest', 'Agrave', 'Aacute', 'Acirc', 'Atilde', + 'Auml', 'Aring', 'AElig', 'Ccedil', 'Egrave', 'Eacute', + 'Ecirc', 'Euml', 'Igrave', 'Iacute', 'Icirc', 'Iuml', + 'ETH', 'Ntilde', 'Ograve', 'Oacute', 'Ocirc', 'Otilde', + 'Ouml', 'times', 'Oslash', 'Ugrave', 'Uacute', 'Ucirc', + 'Uuml', 'Yacute', 'THORN', 'szlig', 'agrave', 'aacute', + 'acirc', 'atilde', 'auml', 'aring', 'aelig', 'ccedil', + 'egrave', 'eacute', 'ecirc', 'euml', 'igrave', 'iacute', + 'icirc', 'iuml', 'eth', 'ntilde', 'ograve', 'oacute', + 'ocirc', 'otilde', 'ouml', 'divide', 'oslash', 'ugrave', + 'uacute', 'ucirc', 'uuml', 'yacute', 'thorn', 'yuml', + 'quot', 'amp', 'lt', 'gt', 'apos', 'OElig', + 'oelig', 'Scaron', 'scaron', 'Yuml', 'circ', 'tilde', + 'ensp', 'emsp', 'thinsp', 'zwnj', 'zwj', 'lrm', + 'rlm', 'ndash', 'mdash', 'lsquo', 'rsquo', 'sbquo', + 'ldquo', 'rdquo', 'bdquo', 'dagger', 'Dagger', 'permil', + 'lsaquo', 'rsaquo', 'euro', 'fnof', 'Alpha', 'Beta', + 'Gamma', 'Delta', 'Epsilon', 'Zeta', 'Eta', 'Theta', + 'Iota', 'Kappa', 'Lambda', 'Mu', 'Nu', 'Xi', + 'Omicron', 'Pi', 'Rho', 'Sigma', 'Tau', 'Upsilon', + 'Phi', 'Chi', 'Psi', 'Omega', 'alpha', 'beta', + 'gamma', 'delta', 'epsilon', 'zeta', 'eta', 'theta', + 'iota', 'kappa', 'lambda', 'mu', 'nu', 'xi', + 'omicron', 'pi', 'rho', 'sigmaf', 'sigma', 'tau', + 'upsilon', 'phi', 'chi', 'psi', 'omega', 'thetasym', + 'upsih', 'piv', 'bull', 'hellip', 'prime', 'Prime', + 'oline', 'frasl', 'weierp', 'image', 'real', 'trade', + 'alefsym', 'larr', 'uarr', 'rarr', 'darr', 'harr', + 'crarr', 'lArr', 'uArr', 'rArr', 'dArr', 'hArr', + 'forall', 'part', 'exist', 'empty', 'nabla', 'isin', + 'notin', 'ni', 'prod', 'sum', 'minus', 'lowast', + 'radic', 'prop', 'infin', 'ang', 'and', 'or', + 'cap', 'cup', 'int', 'sim', 'cong', 'asymp', + 'ne', 'equiv', 'le', 'ge', 'sub', 'sup', + 'nsub', 'sube', 'supe', 'oplus', 'otimes', 'perp', + 'sdot', 'lceil', 'rceil', 'lfloor', 'rfloor', 'lang', + 'rang', 'loz', 'spades', 'clubs', 'hearts', 'diams', + ); + + $allowedposttags = array_map( '_wp_add_global_attributes', $allowedposttags ); +} else { + $allowedtags = wp_kses_array_lc( $allowedtags ); + $allowedposttags = wp_kses_array_lc( $allowedposttags ); +} + +/** + * Filters content and keeps only allowable HTML elements. + * + * This function makes sure that only the allowed HTML element names, attribute + * names and attribute values plus only sane HTML entities will occur in + * $string. You have to remove any slashes from PHP's magic quotes before you + * call this function. + * + * The default allowed protocols are 'http', 'https', 'ftp', 'mailto', 'news', + * 'irc', 'gopher', 'nntp', 'feed', 'telnet, 'mms', 'rtsp' and 'svn'. This + * covers all common link protocols, except for 'javascript' which should not + * be allowed for untrusted users. + * + * @since 1.0.0 + * + * @param string $string Content to filter through kses + * @param array $allowed_html List of allowed HTML elements + * @param array $allowed_protocols Optional. Allowed protocol in links. + * @return string Filtered content with only allowed HTML elements + */ +function wp_kses( $string, $allowed_html, $allowed_protocols = array() ) { + if ( empty( $allowed_protocols ) ) + $allowed_protocols = wp_allowed_protocols(); + $string = wp_kses_no_null($string); + $string = wp_kses_js_entities($string); + $string = wp_kses_normalize_entities($string); + $string = wp_kses_hook($string, $allowed_html, $allowed_protocols); // WP changed the order of these funcs and added args to wp_kses_hook + return wp_kses_split($string, $allowed_html, $allowed_protocols); +} + +/** + * Return a list of allowed tags and attributes for a given context. + * + * @since 3.5.0 + * + * @param string $context The context for which to retrieve tags. Allowed values are + * post | strip | data | entities or the name of a field filter such as pre_user_description. + * @return array List of allowed tags and their allowed attributes. + */ +function wp_kses_allowed_html( $context = '' ) { + global $allowedposttags, $allowedtags, $allowedentitynames; + + if ( is_array( $context ) ) + return apply_filters( 'wp_kses_allowed_html', $context, 'explicit' ); + + switch ( $context ) { + case 'post': + return apply_filters( 'wp_kses_allowed_html', $allowedposttags, $context ); + break; + case 'user_description': + case 'pre_user_description': + $tags = $allowedtags; + $tags['a']['rel'] = true; + return apply_filters( 'wp_kses_allowed_html', $tags, $context ); + break; + case 'strip': + return apply_filters( 'wp_kses_allowed_html', array(), $context ); + break; + case 'entities': + return apply_filters( 'wp_kses_allowed_html', $allowedentitynames, $context); + break; + case 'data': + default: + return apply_filters( 'wp_kses_allowed_html', $allowedtags, $context ); + } +} + +/** + * You add any kses hooks here. + * + * There is currently only one kses WordPress hook and it is called here. All + * parameters are passed to the hooks and expected to receive a string. + * + * @since 1.0.0 + * + * @param string $string Content to filter through kses + * @param array $allowed_html List of allowed HTML elements + * @param array $allowed_protocols Allowed protocol in links + * @return string Filtered content through 'pre_kses' hook + */ +function wp_kses_hook( $string, $allowed_html, $allowed_protocols ) { + $string = apply_filters('pre_kses', $string, $allowed_html, $allowed_protocols); + return $string; +} + +/** + * This function returns kses' version number. + * + * @since 1.0.0 + * + * @return string KSES Version Number + */ +function wp_kses_version() { + return '0.2.2'; +} + +/** + * Searches for HTML tags, no matter how malformed. + * + * It also matches stray ">" characters. + * + * @since 1.0.0 + * + * @param string $string Content to filter + * @param array $allowed_html Allowed HTML elements + * @param array $allowed_protocols Allowed protocols to keep + * @return string Content with fixed HTML tags + */ +function wp_kses_split( $string, $allowed_html, $allowed_protocols ) { + global $pass_allowed_html, $pass_allowed_protocols; + $pass_allowed_html = $allowed_html; + $pass_allowed_protocols = $allowed_protocols; + return preg_replace_callback( '%(|$))|(<[^>]*(>|$)|>)%', '_wp_kses_split_callback', $string ); +} + +/** + * Callback for wp_kses_split. + * + * @since 3.1.0 + * @access private + */ +function _wp_kses_split_callback( $match ) { + global $pass_allowed_html, $pass_allowed_protocols; + return wp_kses_split2( $match[0], $pass_allowed_html, $pass_allowed_protocols ); +} + +/** + * Callback for wp_kses_split for fixing malformed HTML tags. + * + * This function does a lot of work. It rejects some very malformed things like + * <:::>. It returns an empty string, if the element isn't allowed (look ma, no + * strip_tags()!). Otherwise it splits the tag into an element and an attribute + * list. + * + * After the tag is split into an element and an attribute list, it is run + * through another filter which will remove illegal attributes and once that is + * completed, will be returned. + * + * @access private + * @since 1.0.0 + * @uses wp_kses_attr() + * + * @param string $string Content to filter + * @param array $allowed_html Allowed HTML elements + * @param array $allowed_protocols Allowed protocols to keep + * @return string Fixed HTML element + */ +function wp_kses_split2($string, $allowed_html, $allowed_protocols) { + $string = wp_kses_stripslashes($string); + + if (substr($string, 0, 1) != '<') + return '>'; + # It matched a ">" character + + if ( ''), '', $string ); + while ( $string != ($newstring = wp_kses($string, $allowed_html, $allowed_protocols)) ) + $string = $newstring; + if ( $string == '' ) + return ''; + // prevent multiple dashes in comments + $string = preg_replace('/--+/', '-', $string); + // prevent three dashes closing a comment + $string = preg_replace('/-$/', '', $string); + return ""; + } + # Allow HTML comments + + if (!preg_match('%^<\s*(/\s*)?([a-zA-Z0-9]+)([^>]*)>?$%', $string, $matches)) + return ''; + # It's seriously malformed + + $slash = trim($matches[1]); + $elem = $matches[2]; + $attrlist = $matches[3]; + + if ( ! is_array( $allowed_html ) ) + $allowed_html = wp_kses_allowed_html( $allowed_html ); + + if ( ! isset($allowed_html[strtolower($elem)]) ) + return ''; + # They are using a not allowed HTML element + + if ($slash != '') + return ""; + # No attributes are allowed for closing elements + + return wp_kses_attr( $elem, $attrlist, $allowed_html, $allowed_protocols ); +} + +/** + * Removes all attributes, if none are allowed for this element. + * + * If some are allowed it calls wp_kses_hair() to split them further, and then + * it builds up new HTML code from the data that kses_hair() returns. It also + * removes "<" and ">" characters, if there are any left. One more thing it does + * is to check if the tag has a closing XHTML slash, and if it does, it puts one + * in the returned code as well. + * + * @since 1.0.0 + * + * @param string $element HTML element/tag + * @param string $attr HTML attributes from HTML element to closing HTML element tag + * @param array $allowed_html Allowed HTML elements + * @param array $allowed_protocols Allowed protocols to keep + * @return string Sanitized HTML element + */ +function wp_kses_attr($element, $attr, $allowed_html, $allowed_protocols) { + # Is there a closing XHTML slash at the end of the attributes? + + if ( ! is_array( $allowed_html ) ) + $allowed_html = wp_kses_allowed_html( $allowed_html ); + + $xhtml_slash = ''; + if (preg_match('%\s*/\s*$%', $attr)) + $xhtml_slash = ' /'; + + # Are any attributes allowed at all for this element? + if ( ! isset($allowed_html[strtolower($element)]) || count($allowed_html[strtolower($element)]) == 0 ) + return "<$element$xhtml_slash>"; + + # Split it + $attrarr = wp_kses_hair($attr, $allowed_protocols); + + # Go through $attrarr, and save the allowed attributes for this element + # in $attr2 + $attr2 = ''; + + $allowed_attr = $allowed_html[strtolower($element)]; + foreach ($attrarr as $arreach) { + if ( ! isset( $allowed_attr[strtolower($arreach['name'])] ) ) + continue; # the attribute is not allowed + + $current = $allowed_attr[strtolower($arreach['name'])]; + if ( $current == '' ) + continue; # the attribute is not allowed + + if ( strtolower( $arreach['name'] ) == 'style' ) { + $orig_value = $arreach['value']; + $value = safecss_filter_attr( $orig_value ); + + if ( empty( $value ) ) + continue; + + $arreach['value'] = $value; + $arreach['whole'] = str_replace( $orig_value, $value, $arreach['whole'] ); + } + + if ( ! is_array($current) ) { + $attr2 .= ' '.$arreach['whole']; + # there are no checks + + } else { + # there are some checks + $ok = true; + foreach ($current as $currkey => $currval) { + if ( ! wp_kses_check_attr_val($arreach['value'], $arreach['vless'], $currkey, $currval) ) { + $ok = false; + break; + } + } + + if ( $ok ) + $attr2 .= ' '.$arreach['whole']; # it passed them + } # if !is_array($current) + } # foreach + + # Remove any "<" or ">" characters + $attr2 = preg_replace('/[<>]/', '', $attr2); + + return "<$element$attr2$xhtml_slash>"; +} + +/** + * Builds an attribute list from string containing attributes. + * + * This function does a lot of work. It parses an attribute list into an array + * with attribute data, and tries to do the right thing even if it gets weird + * input. It will add quotes around attribute values that don't have any quotes + * or apostrophes around them, to make it easier to produce HTML code that will + * conform to W3C's HTML specification. It will also remove bad URL protocols + * from attribute values. It also reduces duplicate attributes by using the + * attribute defined first (foo='bar' foo='baz' will result in foo='bar'). + * + * @since 1.0.0 + * + * @param string $attr Attribute list from HTML element to closing HTML element tag + * @param array $allowed_protocols Allowed protocols to keep + * @return array List of attributes after parsing + */ +function wp_kses_hair($attr, $allowed_protocols) { + $attrarr = array(); + $mode = 0; + $attrname = ''; + $uris = array('xmlns', 'profile', 'href', 'src', 'cite', 'classid', 'codebase', 'data', 'usemap', 'longdesc', 'action'); + + # Loop through the whole attribute list + + while (strlen($attr) != 0) { + $working = 0; # Was the last operation successful? + + switch ($mode) { + case 0 : # attribute name, href for instance + + if (preg_match('/^([-a-zA-Z]+)/', $attr, $match)) { + $attrname = $match[1]; + $working = $mode = 1; + $attr = preg_replace('/^[-a-zA-Z]+/', '', $attr); + } + + break; + + case 1 : # equals sign or valueless ("selected") + + if (preg_match('/^\s*=\s*/', $attr)) # equals sign + { + $working = 1; + $mode = 2; + $attr = preg_replace('/^\s*=\s*/', '', $attr); + break; + } + + if (preg_match('/^\s+/', $attr)) # valueless + { + $working = 1; + $mode = 0; + if(false === array_key_exists($attrname, $attrarr)) { + $attrarr[$attrname] = array ('name' => $attrname, 'value' => '', 'whole' => $attrname, 'vless' => 'y'); + } + $attr = preg_replace('/^\s+/', '', $attr); + } + + break; + + case 2 : # attribute value, a URL after href= for instance + + if (preg_match('%^"([^"]*)"(\s+|/?$)%', $attr, $match)) + # "value" + { + $thisval = $match[1]; + if ( in_array(strtolower($attrname), $uris) ) + $thisval = wp_kses_bad_protocol($thisval, $allowed_protocols); + + if(false === array_key_exists($attrname, $attrarr)) { + $attrarr[$attrname] = array ('name' => $attrname, 'value' => $thisval, 'whole' => "$attrname=\"$thisval\"", 'vless' => 'n'); + } + $working = 1; + $mode = 0; + $attr = preg_replace('/^"[^"]*"(\s+|$)/', '', $attr); + break; + } + + if (preg_match("%^'([^']*)'(\s+|/?$)%", $attr, $match)) + # 'value' + { + $thisval = $match[1]; + if ( in_array(strtolower($attrname), $uris) ) + $thisval = wp_kses_bad_protocol($thisval, $allowed_protocols); + + if(false === array_key_exists($attrname, $attrarr)) { + $attrarr[$attrname] = array ('name' => $attrname, 'value' => $thisval, 'whole' => "$attrname='$thisval'", 'vless' => 'n'); + } + $working = 1; + $mode = 0; + $attr = preg_replace("/^'[^']*'(\s+|$)/", '', $attr); + break; + } + + if (preg_match("%^([^\s\"']+)(\s+|/?$)%", $attr, $match)) + # value + { + $thisval = $match[1]; + if ( in_array(strtolower($attrname), $uris) ) + $thisval = wp_kses_bad_protocol($thisval, $allowed_protocols); + + if(false === array_key_exists($attrname, $attrarr)) { + $attrarr[$attrname] = array ('name' => $attrname, 'value' => $thisval, 'whole' => "$attrname=\"$thisval\"", 'vless' => 'n'); + } + # We add quotes to conform to W3C's HTML spec. + $working = 1; + $mode = 0; + $attr = preg_replace("%^[^\s\"']+(\s+|$)%", '', $attr); + } + + break; + } # switch + + if ($working == 0) # not well formed, remove and try again + { + $attr = wp_kses_html_error($attr); + $mode = 0; + } + } # while + + if ($mode == 1 && false === array_key_exists($attrname, $attrarr)) + # special case, for when the attribute list ends with a valueless + # attribute like "selected" + $attrarr[$attrname] = array ('name' => $attrname, 'value' => '', 'whole' => $attrname, 'vless' => 'y'); + + return $attrarr; +} + +/** + * Performs different checks for attribute values. + * + * The currently implemented checks are "maxlen", "minlen", "maxval", "minval" + * and "valueless". + * + * @since 1.0.0 + * + * @param string $value Attribute value + * @param string $vless Whether the value is valueless. Use 'y' or 'n' + * @param string $checkname What $checkvalue is checking for. + * @param mixed $checkvalue What constraint the value should pass + * @return bool Whether check passes + */ +function wp_kses_check_attr_val($value, $vless, $checkname, $checkvalue) { + $ok = true; + + switch (strtolower($checkname)) { + case 'maxlen' : + # The maxlen check makes sure that the attribute value has a length not + # greater than the given value. This can be used to avoid Buffer Overflows + # in WWW clients and various Internet servers. + + if (strlen($value) > $checkvalue) + $ok = false; + break; + + case 'minlen' : + # The minlen check makes sure that the attribute value has a length not + # smaller than the given value. + + if (strlen($value) < $checkvalue) + $ok = false; + break; + + case 'maxval' : + # The maxval check does two things: it checks that the attribute value is + # an integer from 0 and up, without an excessive amount of zeroes or + # whitespace (to avoid Buffer Overflows). It also checks that the attribute + # value is not greater than the given value. + # This check can be used to avoid Denial of Service attacks. + + if (!preg_match('/^\s{0,6}[0-9]{1,6}\s{0,6}$/', $value)) + $ok = false; + if ($value > $checkvalue) + $ok = false; + break; + + case 'minval' : + # The minval check makes sure that the attribute value is a positive integer, + # and that it is not smaller than the given value. + + if (!preg_match('/^\s{0,6}[0-9]{1,6}\s{0,6}$/', $value)) + $ok = false; + if ($value < $checkvalue) + $ok = false; + break; + + case 'valueless' : + # The valueless check makes sure if the attribute has a value + # (like ) or not (